Stockholm has an extensive network of metros, commuter trains, buses and trams that are operated by the Storstockholms Lokaltrafik.
The metro or tunnelbana is the heart of the system with trains running daily from 5am till 1am and even later at the weekends. The metro is linked with the commuter train service which, however, is not that frequent.
Storstockholms Lokaltrafik (SL)
Telephone: (08) 600 1000

The SL Tourist Card grants free travel on all modes of public transport inside Greater Stockholm and costs SKr95 for a 24-hour validity and SKr180 for a 72-hour validity pass. The Stockholmskortet grants free access along with some other benefits and costs SKr260 for a 24-hour pass, SKr390 for a 48-hour pass, and SKr540 for a 72-hour pass, and is easily available at the Stockholm Information Service offices.